Eco-benign enzymatic dehairing of goatskins utilizing a protease from a Pseudomonas fluorescens species isolated from fish visceral waste

Abstract

The dehairing of skin/hide is the most polluting process of all leather manufacturing processes. In this study, an attempt has been made to extract a crude bacterial protease from fish visceral wastes and to utilize the protease to dehair goatskins. The bacterial species isolated has been identified by biochemical tests and microscopic examination as Pseudomonas fluorescens. The optimum pH and temperature conditions for the maximal activity of the extracted crude protease have been determined to be 10.5 and 40 °C, respectively. It has been found that a combination of the extracted crude protease with a small amount of sodium sulfide allows for the complete dehairing of goatskins without the use of lime. The enzyme-dehaired goat leathers were evaluated by mechanical, touch–visual and by electron microscopy and were compared to conventionally dehaired goat leathers. The results indicate that the enzyme-dehaired leathers exhibit similar or improved characteristics. In essence, this report provides a do-only, eco-friendly approach to cleaner leather processing by utilizing natural resources derived from fish-industry biowastes, which may reduce the leather industry’s generation of toxic chemical wastes.